Environmental & Genetic Influences on Vitamin D Status

Vitamin D Deficiency Clinical Trial

Official title:

Environmental & Genetic Influences on Vitamin D Status

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01208636
• Other study ID #: Creighton9
• Status: Completed
• Phase: N/A
• First received: August 30, 2010
• Last updated: September 23, 2010
• Start date: August 2010
• Est. completion date: August 2010

Study information

• Verified date: September 2010
• Source: Creighton University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

The purpose of this study is to determine the effect of environmental and genetic influences on Vitamin D status.

Description:

Vitamin D deficiency is a common problem. The principal source of vitamin D for humans is solar exposure, with cutaneous synthesis of vitamin D by photoconversion of 7-dehydrocholesterol in the skin to pre-vitamin D3. Latitude, altitude, season, skin pigmentation, and age are recognized factors that influence how much vitamin D can be made by solar exposure. Surprisingly, Vitamin D deficiency has been described in people dwelling in southern Florida and in surfers in Hawaii. We hypothesize that genetic variations in vitamin metabolism accounts for these differences.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: August 2010
• Est. primary completion date: August 2010
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• Able to consent and come for a study visit.

• Male or female between ages 18-60.

• Sun exposure >3 hours daily for at least 5 days weekly for the last 3 months.

Exclusion Criteria:

• Unable to consent or come to a visit

• Taking Vitamin D supplements, anticonvulsants, barbiturates, steroids, having granulomatous disease, or liver or kidney disease as these medications and conditions interfere with Vitamin D metabolism.

• Related to another participant by blood.

Study Design

Observational Model: Cohort, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Vitamin D Deficiency

Locations

Country	Name	City	State
United States	Creighton University	Omaha	Nebraska

Sponsors (2)

Lead Sponsor	Collaborator
Creighton University	Procter and Gamble

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	25(OH)D levels	25(OH)D levels were measured at the only visit	1 month	No
Secondary	Genetic testing of 13 candidate genes	13 candidate genes were tested and their relationship to 25(OH)D examined.	1 month	No